1. Field of the Invention
The present invention relates to an optical touch panel which enables coordinate inputting by a finger or a pen and includes a coordinate input region composed of a display screen, such as a liquid crystal panel or the like, and a light-emitting element, a light-receiving element, and an optical waveguide which are provided around the coordinate input region.
2. Description of Related Art
Optical touch panels are widely used for bank ATM systems or railway ticket-vending machines and the like because the display screens are clear and excellent in reliability compared with resistive touch panels and capacitance-type touch panels. Optical touch panels in which a large number of light-emitting diodes and phototransistors are arranged around a coordinate input region, are known (Japanese Unexamined Patent Publication No. 11-232024 A). Further, optical touch panels in which optical waveguides and microlenses are provided around the coordinate input region are known (Japanese Unexamined Patent Publication No. 2004-295644 A). Conventional optical touch panels have had, however, a problem with poor input operational feeling (click touch feeling), resulting in insufficient comfortableness in operation and certainty.
It is therefore an object of the present invention to provide an optical touch panel which can obtain natural input operational feeling (click touch feeling) and has operation certainty.